Telephone-exchange system.



H'. H.1STROUD TELEPHONE 'E XGHANGE SYSTEM. APPLICATION FILED JULY 25.:901.

- Pai'ented Dec. 17, 1918.

I 27a a2 ,2). Liz/i0 d, w

UN T STAT .ATENT ()FFICE.

HAROLD D. STROUD, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

KELLOGG 'SWIZTCHBOARD.& SUPPLY COMPtNY, A CGRPORATION OF ILLINOIS.

TELEPHONE-EXCHANGE SYSTEM.

incense.

Specification "of Ietters Patent.

Patented Dec. 17. 1918.

Application filed July 25, 1901. Serial No. 69,681.

To all whom it mayconce'rn Be it known that I, HAROLD D. STnoUn,

' a citizen of the United States, residing at Chicago, in-the county of Cook and State of Illinois, haveinventcd a certain new and useful Improvement in Telephone-Exchange 1 change systems, and has for its object the provision of automatic means for connecting subscribers telephone lines with c ord circuits, which cord circuits are also .provlded with manually operated means foruniting the same with telephone linesfor completing connection between subscribers.

By means of my invention, I am-enabled to have the calling subscribers line auto- ,matically connected with the answering end of the cord circuit, the connecting end of the cord circuit being preferably provided with a connecting plug adapted for inser tion within any of the ordinary l ne jacks.

- To this end, I preferably equip each sub scribers line with a traveling springjackadapted to be operated through the agency opt apparatus actuated when a call is initiated, which springjack in its movement is brought into connection with the terminals of an idle cord-circuit at the answering "end thereof, whereupon an electromagnet c device has its operative condition changed to check the further movement of the traveling springjack-to maintain the same in engagement with the saidcord circuit terminals,

whereby the cord circuit constitutes a continuation of the calling subscribers line,

the springj ackibeing provided with springs connected with the sides of the said'telephone line. The telephone lines are preferably unprovided with an individual line controlled thereby, the signal being preferably in the form of a small incandescent electric lamp, though I do not wishto be limited to this character of signal. The operator, aft'erhaving communicated with the calling subscriber, through the agency other telephonic outfit, inserts the connecting plug connected with the cord circuit to which the said signal corresponds, whereupon signaling' current may be directed'over the called subscribers telephone line to actuate it's signal. The clearing-out signal is preferably manifested by the same indicator. In order to effect a disconnection between the cord circuit and the calling subscribers telephone line, I preferably employ an instrumentality governed in its operation bymeans of the connecting plug, which plu upon being withdrawn from the called subscribers springj ack, serves toactuate the said instrume'ntality to elfect a travel of the calling subscribers moving springjack out of .connection with the terminals at the answering end of the cord circuit, whereupon an electromagnet, preferably forming a part of the said instrumentality, is brought intoplay to stop the moving springjack, whereupon the cord circuit-is restored to its normal condition, so that it may be automatically connected with another calling subscriber.

The advantages I gain by the apparatus of my invention are numerous.

In the first place, the operators attention is confined to but one plug of each cord circuit. \Vhen the system is employed'in connection with multiple switchboards, the especi-ally provided answering jacksof the form now so well known may be dispensed with. Individual line signals for each telephone line are also rendered unnecessary, as they are prgferably replaced by the reduced number of indicators employed only in connection with the cord circuits. This elimination of line acks and individual line indicators for eachtelephone line lessens the attention the operator has to bestow upon the various signals and switches of the system. The capacity of switchboards by means of the invention may be increased, and the time for completing and breaking connections is greatly reduced, enabling the operator to increase her capacity."

I will explain the preferred embodiment of my invention in connection with the accompanying drawing, in which Figure 1 illustrates a multiple switchboard teiephoneexchange system, having a semi-automatically controlled cord circuit constructed in accordance with the invention;

' Fig. 2'is a detailed plan view of a motor and associated parts "for actuating the mov- ,ing springjack;

Fig. 3'is aside elevation looking in the direction of arrow 3 in F ig. '2.

,'i ;.trated one type of telephone substation ap? 'paratus, which isvwell understood by those At substations 90 and 120 I have illus- -skilled in the art, there being illustrated at each substation a gravity switchhook 1, prowidedwith a normal contact constituting a terminal of a branch including a signal hell 2 and a condenser 3,'and an alternate v contact constituting a terminal of a branch "including the primary 4: of an induction coil and the transmittter 5, the secondary 6 of the induction coil being included in the local circuit with a receiver 7. When the receiver is upon its switch hook the limbs 8 and 9 of the telephone line are united by means of the branch including the signal bell and con- .denser. When the receiver is removed from its hook, the said limbs are united by the bra ch including the transmitter and the primary of/the induction coil. The limbs 8 and 9 extend to the exchange,'and, in the case of multiple switchboards, are united with any usual form of line jacks 10, 10 upon the different sections of the particular board. The invention, however, is not to be limited to multiple switchboard systems. In

' the case of all switchboards each subscribers telephone line is preferably provided with an additional springjack acting as a selector which is adapted to travel so as to seek the answering end of-a cord circuit or connector rather than be manually sought by the answering end of the cord circuit, as hitherto.

respectively being mounted upon the arm but insulated from each other. The traveling springjack and the mechanism for operating the same are diagrammatically indicated in F ig. 1, their preferred structural form being illustrated in Figs. 2 and 3. Two

peripheral rows of contacts, l4 and 15, are provided, with which the springs 12 and 13 are adapted for successive engagement. The radially alined contacts 14 and 15 of the switching appliance illustrated in Fig. 1 and the. axially alined contacts 14 and 15 of the preferred form of the switching appliance illustrated in Figs. 2 and 8, are adapted for simultaneous engagement withv the jack v springs 12 and 1.3 rmpectively. Each of $5 the s'e pairs of alined opntacts constitute the terminals of the answering end of a corre-f-L but one cord circuit completely, but Ihave sWeringcontac'ts-to another cord circuit.

Each cord circuit is provided with a single connecting terminal plug 16 and a plurality of pairs of answering terminals 14: and 15 "sponding cord circuit. I have illustrated.

' indicated the connection of two pairs of anin multiple relation, for the purpose of providing a set of answering cord Circuit 0011- tacts for each traveling springjack. In Fig. 1 two pairs of answering terminal contacts; are illustrated in multiple relation, .and; 1

branches l7, 17 for connection with other pairs of answering contacts are indicated;

into the service of connecting and. discon-' necting subscribers lines. 4

To eiiect the travel of the arm 11 carrying the moving springjack, I preferably employ a motor 18, which may be a self-winding spring motor or motor of other type. This motor actuates a worm shaft '19, having engagement with a worm wheel 20, from which projects the arm 11, carrying the springs of the corresponding answering springjacks. These springs'are connected with a pair of collector rings 20 and 21, with which con-.

tact brushes 22 and 23 are engaged, which contact brushes are directly connected with the line. The motor actuates a number of fan blades 24, across whose plane the nose 25, carried upon the armature 26, projects when the electromagnet 27, controlling the said armature, is deenergized, whereby the said worm shaft is held from rotation to secure the springs of the springjack in a stationary position, the said springs being normally disconnected from answering contacts of the cord circuit when the cord circuit is idle, as will be hereinafter explained. iVhen a subscriber'initiatcs a call, the electromagnet 27 is energized by being included in circuit with the common battery 28, occurring when the calling subscriber removes his telephone from its switch hook, this battery being eX- cluded from circuit with the electromagnet when the telephone .is upon its switch hook by the condenser included in the bell branch. The magnet, upon being thus energized, attracts its armature and removes the nose 25 from'engagement with the fan blades 24,

whereupon the motor 18 is permitted to 0pcrate to rotate the springjack upon the arm 11 into engagement with a pair of answering contacts 14, 15, the traveling springjack selecting a pair of answering contacts of the .line cord circuit in'the manner to be presently set forth. i

The cord circuit is, in this instance, provided witha tip strand 29, connected with lamp. The armature 3l, by resting on its.

normal contact, excludes thelamp'33 from a circuit; by engaging its alternate contact, it 'includesthe lamp 33 in c1rcu1t. 'The armature of the inagnet 32*and its contact anvil are in series in the branch conductorincluding the signal VVhena cord circuit is idle, the corresponding contact 14: is

- connected with one terminal of the common battery by way of the Winding of relay 31, its armature, the normal contact anvil for the armature, the branch conductor 34, the spring of a plug seat switch, and a branch conductor 36. If the cord circuit were-busy, that is, werc in use in connecting other subiscribers lines for conversation, the armatures of both electromagnets 31 and 32 would be attracted, thereby disconnecting the conductor 34 and the terminal of the battery connected with the said conductor from the particular sleeve strand connected with a. contact 14. It, therefore, the moving spring- .Ja'ckspring 12 comes into engagement with the contact 1% that is not thus connected with a terminal of the battery 28, it will continue in its travel until it does strike a contact that is connected with this battery terminal, whereupon circuit may be'traced from. the engaging contact 1l,"the winding 31, the lamp 33, the armature of magnet 32, the conductor 3%, switch spring 35, conductor 36, to one terminal of the battery .28 thence from this battery through the wmdn g of the electromagnet back'to the said jack spring 12. The circuit just tracedqthrough the winding 31 and thelamp 33 is a maintaining circuit for relay 37 and immediately replaces the initial energizing circuit, which is by way of the winding of relay 31. its armature and the normal contact anvil for the armature. The magnet or relay 37 is thus energized, when an idle cordcircuithas been thus antomatically selected. to attract armature from its contact anvil to open circuit through the magnet27, thereby permitting the nose to be thrust into the path of the It will be observed that the magnet 37 is of very low winding, so that owing to the resistance of the line, transmitter at the subscribers. station, and the otherinstrumentalities in the circuit, this magnet 37' is the arm 11 to rest. The lamp 33 is, simul- .necting plugjl6 intrras-stationary jack 10 of magnets 27,37 to the common batterv 28.

not energized when a subscriber initiates a call, whereby the selector magnet 27 may.

be permitted to perform its function. When,

however,.a local, circuit offlow resistance is established by the connection of the spring 12 with a eontactlt of an idle-cord-circuit, sufficient current will be :passed through this magnet 37 topermit it to open 'the'ci'rcui't including the magnet 27 to '.-arrest the fur-1 ther operation of the motor 18' andpermit taneously with the energization of the mag-'- net 37, caused to'glow, warning the operator that the cord circuit corresponding to the lamp has been automatically selected by a For this purpose, I have illustrated a manually operated listening key 38. Supposing, for example, that subscriber No. is the calling subscriber, and that he Wishes connection with subscriber No. 120; the Y operator, after operating key 38 removes the plug 16 'from its seat, and inserts the conthe called subsc'ribers line, and at the same time includes a signaling generator 40 in bridge of the cord circuit. '1 have illustrated a manually operated ringing key 41 for this latter purpose. I do not wish to be limited, however, to the manual operation of either or bot-h keys 38 and 41. When the called subscriber responds by removing his telephone from its switch hook, circuit is'also closed throughthe magnet 32, thereby opening the circuit including the lamp A line relay 42 is provided in connection' witheach telephone line, this relay beins" provided with'two armatures which normallypreserve the connection of the electro- The connecting plug, however, is provided with a third contact adapted for engagement with the'thimble 13- of a line jack,'. whereby a local circuit including the conductor. 36, the said battery and the relay 42, is established, the armature's of the said relay being attracted to disconnect thenragnets-27 and 37 from the common battery,- whereby the operation of the selector mag- 5 net 27 of the called subscribers line is prevented when the calledv subscriber removes his telephone from its switch hook. The connecting plug,,having been withdrawn from engagement withits plug seatswitch,releases the plug switch spring 44 to permit. it to engage its alternate contact anvil and include impedence i5 111 clrcuit with the battery 28.

After the subscribers have finished con- I rersation, their receivers being restored. current through the magnet 32 ceases to flow but continues to flow through the magnet 31, the circuit through the latter magnet being traced fronr one pole of the battery 28 to 30' magnet 37 f the calling subscriber, the

I spring. 12, the engaging contact 14, the mag.

net winding 31, electric lamp 33, the armature of the electromagnet 32, the conductor- 5 34:, the spring 35, conductor 36, to the other pole of the battery 28. The operator there- 7 upon restores the plug i6 to, its seat, and in so doing momentarily dlsengages the spring 35 fromthe terminal connected with the con- 10 ductor 36. The connection, however, is im- 1'5 ripheral groove adapted for engagement with a bend in the spring 35.

' To. reset the moving sprmgjack of the calling subscriber, the spring 44 through.

the agency of the restored plug connects a 2o" conductor 45' across the cord circuit, and, as

the corresponding magnet 37 is deenergized, completes circuit through the selector magnet 27, Whose armature is attracted to permit the motor 18 to operate. Current from battery 28 flows by way of 45', 44, tip strand of the cord to contact 15, spring 13, magnet 27 and back tobattery 28 to reset the moving jack. The arm llis thereupon moved until the brushes 12 and 13 are removed 30 from engagement with the engaging contacts l4 and '15, whereupon, circuit through i the electromagnet 27 is opened to release ts armature and prevent the further operation of the said motor.

It will be seen that I have provided a telephone exchange system wherein the selecting mechanism includes traveling contacts that automatically connect calling lines with the answering ends of cord or link- 40 circuits, which link circuits have manually controlled terminals, preferably in the form of plugs. It will also be seen that the call signals are automatically controlled'and are adapted for interchangeable association with different telephone lines, The manually controlled terminals of the link circuits operate upon the signal devices (which are preferably self restoring) v and cause the same to change their indications, this result being preferably accomplished by having these manually controlled terminals operate Y upon circuits of said signal devices.

Where in the claims I use terms like pro-.

gressively traveling switch or automatic .55 progresslvely selective or mechanism including a traveling member or traveling contact maker, I refer to selector mechaanisni having a traveling member capable of assuming a plurality of selective positions 0 as distinguished from simple mechanism,

like a relay for example, having only a simple forward and backward movement.-

While I have herein shown and particularly described thepreferred embodiment of my invention, I do notwish to be limited in multiply springjack for each telephone line adapted. 100

. exchange, of a plurality of cord circuits at the exchange, each including a manually operated. terminal connecting plug, a plurality of sets ofanswering switch contacts connected to the said cord circuits, the an- .swering contacts of the difi'erent cord circuits being arranged in multiply related groups, a moving springjack for each tele phone line adapted forsuccessive connec- 80. tion with: the cord circuits by engagement with the answering contacts, motor mechanism for efi'ecting the travel of the moving springjack, and means associated with each telephone line whereby the calling sub: scriber may control the operation of the motor mechanism to efi'ect the connection of the moving springjack with the answering endof the cord circuit, substantially as described.

2. The combination with telephone lines extending from subscribers stations to an exchange, of a plurality of cord circuits at the exchange, each including a terminal connecting plug, a plurality of'sets of answering swltch contacts connected to the said cord circuits, the answering contacts of the different cord circuits being arranged related groups, a movin for connection with the cord circuits by engagement with the answering contacts, motor mechanism for effecting the travel of themoving springjack, means associated with each telephone line whereby the calling subscriber may control the operation of the motor mechanism to effect the connection of the moving springjack with the an swering end of the cord circuit, an electromagnet associated with each moving springjack for arresting the travel of the spring-v jack, when it is brought into engagement with an idle cord circuit, and switching means controlled by the connecting plug of each cord circuit for governing the circuit of the said electromagnet to permit the passage of the said moving springjack past the answering contacts of busy cord circuits andto arrest the travel of the springjack when brought into engagement with the answering contacts of an idle cord circuit, substantially as described. I

3. The combination with telephone lines extending from subscribers" stations to an exchange, of a plurality of cord circuits at the exchange, each including a terminal connecting plug, a plurality of sets of answering switcr contacts connected to the said cord circuits, the answering contacts of the different cord circuits being arranged 30 vin multiply related groups, a moving springjack for each telephoneline adapted for connection with the cord circuits by engagement with the answering contacts,

motor mechanism for effecting the travel (,jmultiply related groups, a'moving spring:

of the moVingspringjack, means associated with each telephone line whereby the calling subscriber may control the operation of the motor mechanism toefi'ect the connection of the moving-springjack with the an-- swering end of the cord circuit, an electro ,magnet assoclated with each moving sprmg jack for arresting the travel of the spring- ]ack' when it is brought into engagement with an idlecord circuit, and a plug. seat switch for each cord circuit engaged by the corresponding connecting plug when idle for governing the eirc'uit of the said electromagnet to permit the passage of the said moving springjack past the answering contaets of busy cord clrcuits and to arrest the travel of the 'springjack when brought into engagement with the answering contacts .of an idle cord circuit, substantially as de scribed. 4. The combination with telephone lines extending from subscribers. stations to,an

exchange, of a plurality of cord circuits at the exchange, each including a terminal connecting plug, a plurality of sets of answering switch contacts connected to the said cord circuits, the answering contacts of the different cord circuits being arranged in multiply related groups, .a movin springjack for eachtelephone line adapted for connection with the cord circuits by .en-

gagement with the answering contacts,

motor'mechanism for effecting the travel of the moving springjack, means associated with each telephone line whereby the calling subscriber may control the operation of the motor mechanism to effect the \connection of the moving sprmgpck with the an swering end of the cord circuit, an electromagnet associated with each moving spring jack 'for arresting the travel of the spring jack when it is brought into engagement with an idle cord circuit, means controlled by the connecting plug of each cord circuit for governing the circuit of the said electro' magnet to permit the passage of the said moving springjack past the answering contacts of busy cord circuits and to arrest the travel of the springjack when'brought into engagement with the answering contacts of an idle cord circuit, and means governed by the said terminal plug for effecting the restoration of the moving springjack when the sa d connecting plug is disconnected fromthetelephone line, substantially as described. v

5. The combination with telephone line extending from subscribers stations to an exchange, of a plurality of cord circuitsat the exchange each includi g a terminal connecting plug, a plurality of sets of answering' switch contaetsconnected to the said cord circuits, the answering-contacts ofv the different cord circuits being arranged in jack for each telephone line adapted for connection with the cord circuits by engagement with the answering contacts, motor mechanism for effecting the travel of the moving springjack, means associated with each telephone line whereby the calling sub- 5 scriber may control the operation of the motor mechanism to effect-the connection of themoving springjack with the answeringend of the cord circuit, an electromagnet associated with each moving springjack for arresting the travel of the springjack' when it is brought into engagement with an idle cord circuit, means controlled by the connecting plug ofeach cord circuit for governing the circuit of the said eleetro' magnet to permit the passage of the said moving. springmck past the answering con tacts ofbusy cord circuits and to arrest the travel of the springjack when brought into engagement with the answering contacts of an idle cord circuit, and means governed by" the said terminal plug for effecting the res-' toration of the moving springjackwhen the said connecting plug is disconnected from a'telephone line, the latter means including an electromagnet and a circuit-closing switch operated by the connecting plug when restored to permit the travel of the moving 'springja'ck, the said electromagnet being in eluded in circuit with the springj ack, whereby when the springjack is brought out of connection with the answering end of the cord circuit the electromagnet is denergized, checking theffurther progress of the trayeli-ng springjack, substantially as de 6. The combination with telephone lines extending fromsubscribers stations to an eX- changc, of a plurality of cord circuits at the exchange,-each including a terminal connecting plug, a plurality of sets of' answering switch contacts connected to the said cord circuits. the answering contacts of the different cord circuits being arranged in multiply related groups, a. moving springjack for each telephone line adapted for connection with various cordcircuits by engagement with the answering contacts, motor mechanism for effecting the travel of the moving springjack, means associated with each telephone line wherebythe calling subscriber may control the operation of the motorscriber'may control the operation of the mo- 7 The combination'with telephone lines extending from subscribersv stations to an,

exchange, of a plurality of cord circuits at the exchange, each including a terminal connecting plug, a plurality of sets of answering switch contacts connected to the said cord circuits, the answering contacts of the jack for each telephone lineadapted for ment with the answering contacts, motor mechanism for effecting the travel of the moving springjack, means associated withv each telephone line whereby the calling subtor mechanism to effect the connection of the moving springjack with the answering end of the cord circuit, an electromagnet associated with each moving. springiack for arresting the travel of the spring-jack when it' is brought intoengagement with an idle cord circuit, means controlled by the connecting plug of each cord circuit for governing the circuit of the said electromagnet to permit the passage of the said moving springjack past the answering contacts of busv cord circuits andto arrest the travel of the springjack when brought into engage- 6 5; multiply related groups, a moving spring the traveling terminal may make contact,

ment withthe answering contacts of anidle cord circuit, and an indicator in association with each cord circuit and operated upon connection of a moving springjack with the answering end of the selected cord circuit, substantially as described.

jack for each telephone line adapted for connection with the cord circuits by engagement with the answering contacts, motor mechanism for effecting the travel of the moving springja'ck, means associated with each telephone line whereby the calling subscriber may control the operation of the. motor mechanism to effect the connection of the moving springjacli with the answering end of the cord clrcuit, an electromagnet associated with each moving springjack for arresting the travel of the spring] ack when it is brought into engagement with an idle cord'circuit, means controlled by the connecting plug of each cord circuit for governing the circuit of the said electromagnet at one end of the cord circuit, a switching appliance at the other end of the cord circuit,- means controlled by a subscriber for effecting the operation of the said switching 8. The combination with telephone lines extending from subscribers stations to an exchange, of a plurality of cord circuits at the exchange, each including a terminal connecting plug, a plurality ofsets of answer ing switch contacts connected tothe said cord circuits, the answering contacts of the difierent cord circuits being, arranged in multiply related groups, a moving springjack for each telephone line adapted'for con:

nection with the cord circuits by engagement with the answering contacts, motor mechanism for effecting the travel of the moving springjack, means associated with each telephone line whereby the calling subscriber may control the operation of the motor mechanism to eiiect theconnection of the moving springjack with :the answering end of the cord circuit, and a clearing-out indicator included in each cord circuit, substantially as described.

9. The combination with telephone lines extending from subscribers stations to an exchange, of a plurality oftcord circuits at the exchange, each including a terminal connecting plug, a plurality of sets of answering switch contacts connected to the said cord circuits,-the answering contacts of the difi'erent cord circuits being arrangedin appliance to connect the cord circuit with his telephone line, and means controlled by the terminal plug and operated thereby when being restored to its idle condition to efi'ect therestoration of the switching appliance and its disconnection from the said cord circuit, substantially as described.

11. In a telephone exchange system, the conrbinatiomwith a group of telephone line extending from sub-stations to an exchange, of a plurality f cord connectors at the exchange, each including a manually operated terminal plug at one end of the cord circuit and having a travel-ing switch at the other end of the cord circuit and means to propel the traveling switch past undesirable position s, and means serving to arrest the operation of a traveling switch and cause it to connect an idle cord circuit with the telephone line ofa calling subscriber, substantially as described.

12. In a telephone exchange system, the combination with telephone lines extending from sub-stations to an exchange, of a plurality of cord connectors at the exchange, each including a manually operated terminal plug at one end of the cord circuit, a travel ing switching appliance at the other end of the cord circuitand constituting a line terminal, a plurality of contacts for the plurahty of cord clrcuits, with any f which stantially as" described.

and means controlled by a subscriber for governing the traveling switching appliance to connect his line with-a cord circuit, sub-- 13.111; a telephone exchange system, the

com'bination'with a group of telephone lines extending from substations to an exchange,

-. of a plurality: ofcord'connectors at the exchange, each including 'a manually operated terminal plug at 011% end of the-cordcircuit and having a traveling switch at the, other end of the cord circuit, means for propelling .descri'bed.

said traveling contact past undesirable po-i sitions, means serving to arrest the operation of a traveling-switch andcause it to con nectjan idle cord clrcuit with the telephone line of a calling subscriber, and a signal at the exchange controlled byfsaid subscribers apparatus to indicate the fact'of his con-- nection with acord circuit, substantially as 14. In a telephone exchange system, the

' combinationwith telephone lines extending. a from sub-stationsto an exchange, of a plu means controlled by a subscriber for govern ing the traveling swltchin g appliance to'ycOns'cri'bers apparatus, to indicate the fact of his nal plug atone end of the cord circuit, a

nect his line with a cord circuit, and a signal at .the exchange controlled by "said sub.-

connection with a cord circuit, substantially as described. a a v 15. In 'a telephone. exchange system, the combination with a group of telephone lines extending from sub-stations to an exchange, of a plurality of cord connectors at the ex-' change, each including amanually operated terminal plug at one end of the cord circuit and having a traveling switch at the, other end of the cord circuit and means serving to arrest the operation of a traveling switch and cause it toconnect a cord circuit with the telephone line ofafcalling subscriber, and a signal controlled by current in the cord circuit and operated by said sub-- scribers apparatus to indicate the fact of his connection with a cord circuit, substan-- tially as described. v

16. In a telephone exchange system, the

combination with telephone lines extending fIOHTSllb-StiltlODS to an exchange, of a plurality of cord connectors at'theexchange, each including a manually operated termitraveling switching appliance at .the'other end of the cord circuit and constituting a line terminal, a lurality of contacts for the plurality of cor circuits, with any] of which the tra veling'terminal may make contact, [and means controlled by a subscriber governing the traveling switching appliance to connect, his line with --a cord circuit, and signal-controlled by current in the cord circuit and operated by said subscribers apparatus to indicate the fact of his connection with a/cord circuit, substantially as described.

l7. Thecombination with telephone lines extending from subscribers stations to an exchange, of a plurality of link circuits at the exchange, each including a manually operated terminal, a plurality of sets of'answering switch; contactsgconncted to the said link circuits, the'answering contacts of the difierentlink circuits being arranged in multiply related groups, a moving jack for each telephone line adapted for connection with the link circuits by engagement'with the answering contacts, motor. mechanism for effecting the travel of the moving jack past, busy link circuit answering contacts,-

andg'means associated with each telephone line. whereby the calling subscriber may con- .trolthe operation of the motor mechanism I "to e'fl'ect the connection of the moving jack 18. The combinationwith telephone lines extending from subscribers stations to an exchange, of a pluralityof link circuits at with the answering end of an idle link cirtheexchanga'eachincluding a terminal, a lplurality of sets of answering switch contacts connected to the said link circuits, the

answering contacts of the different link cir- -cuits being arranged in multiply related groups, a moving jack for each telephone line adapted for successive connection with the link circuits by engagement with the an--- swering contacts,motor mechanism for ef- -fecting the travel of the moving jack, means associated with each telephone line whereby the calling subscriber may control the operation of the motor mechanism to effect, the

connection or, the moving jack with the answering end of the link circuit, and an in dicator in association with each link circuit and operated upon'connection of a moving jack with the answering end ofthe selected link circuit,

\ 19. The combination with telephone lines extending from subscribers stations to an exchange, of a plurality of link circuits at the exchange, each including a terminal, a plurality of sets of answering switch contacts connected to the said link circuits, the

answering contacts of the different link cir- 1 cuits being arranged in multiply related groups, "a moving 'jack for each telephone line adapted for connection with the link circuits by successive engagement with the busy answering contacts, motor mechanism for effecting the 'trayel of the. moving ack, means associated with each telephone hne Yao whereby the calling subscriber may control the operation of the motor mechanism to efiect the connection of the moving jack with the answering end of an idle link circuit, and a.clearing-out indicator included in each link circuit.

20. In'a telephone exchange system, the combination.with a group of telephone lines f extending from sub-stations to an exchange, 10

change, each including a manually'operated terminal vat one end-of the link circuit an having a traveling switch at the other end of the link circuit, and means serving to arrest the operation of a traveling switch and cause-it-to connect a link'circuit with the telephone line of a calling subscriber.

21; In a telephone exchange system, the combination with telephone lines extending .from sub-stations to an exchange, of a:plu rality of link connectors at the exchange, each including a manual y operated terminal at'one end of the link circuit, a traveling switching appliance at the other end of the link circuit and constituting a line terminal,

' a plurality of contacts for the plurality of link circuits, with any of which the same contact surface of the traveling terminal may make contact, and means controlled by a subscriber for governing the traveling switching appliance to connect his line with a link circuit. I

22. In a telephone exchange system, the combination with a group of telephone lines extending from sub-stations to an exchange, of a plurality of link connectors at the exchange, each including a manually operated terminal at one end of the link circuit and having a traveling switch at the other end of the link circuit, means serving to arrest .the operation of a traveling switch and cause it to connect a link circuit with the telephone line of a calling subscriber, and a signal at the exchange controlled by said subscribers I '45 apparatus to indicate the fact of his con- 'nection with a link circuit.

23. In a telephone exchange system, the,

combination with telephone lines extending from sub-stations to an exchange, of a plurality of link connectors at the exchange, each including a' manually operated terminal at one end oftthe link circuit, a traveling switching appliance at the other end of the link circuit and constituting a line terminal, a plurality of contacts for the plurality of link vcircuits, with any of which the'same contact surface of the traveling terminal .may make contact, and means controlled by a, subscriber for governing the traveling switching'appliance to connect his line with a link circuit, and a signal at the exchange controlled by said subscribers apparatus, to indicate the fact of his connection with a link circuit. I

; 24, In a telephone system, a switch-board,

i ng contacts to said switch-board, means outof aplurality of link connectors at the exa subscribers telephone line, a selective switch for said line, selecting contacts for said switch, waiting contacts for said select- :ing switch, links leading from said waitside of said switch ..for rendering some of said links busy, means for automatically moving said selecting contacts over past the waitingcontacts of busy links, other telephone lines, multiple jacks in said switch-board pertaining to said telephone line, multiple jacks in said switch-board pertaining to said other telephonelines, and connecting means in said switch-board whereby any link may be connected to a multiple jack of a selected line.

25. In a telephone system, a switch-board, a subsc'ribers telephone line, aselective switch for said line, selecting contacts for said. switch, waiting contacts for said select ing switch, links leading from said waiting contacts to said switch-board, means outside ofsaid switch for rendering some of said links busy, means for automatically moving saidselecting contacts over the waiting contacts of the busy links, means for stopping said selecting contacts on the waiting con tacts of the first idle link, other telephone lines, multiple jacks for said telephone line 1 in said switch-board, multiple jacks for said 95 other telephone lines in said switch-board, and plugs forming terminals for said links and adapted to connect with a multiple jack of a selected one of said telephonelines.

26. In a subscribers. telephone line, a selective switch associated therewith, a multiple switch-board, selecting contacts for said selective switch, stationary contacts for said selective switch, a series of links leading from said stationary contacts to said multiple switch-board, and'means for caus ingsaid selective switch to automatically move said selecting contacts into engage ment with the stationary contacts of the first idle link ofsaid series. 110 27. In a telephone system, a subscribers line, a multiple switch-board in which said subscribers line terminates, a selecting. switch for said line, movable trunk hunting contacts upon said switch, stationary con- 11 tacts for said selecting switch, means under the control of the subscribers line for causing said movable contacts to engage certain of said stationary contacts, other subscribers lines terminating in said multiple switch- 0 board, links extending from said stationary contacts to said multiple switch-board, and switching means in said switch-board'whereby any link may be connected with any line.

28. In a telephone system, a switch-board, 125 a subscribers telephone line, a selective switch for said line, selecting contacts "for said switch, waiting contacts for said selecting switch, linksleading from aid waiting contacts to said vswitclqvboard,means torautomatically'moving said selecting contacts past the waiting contacts of busv links,

other telephone lines, multiple jacks in said switch-board pertaining to said telephone line, multiple jacks in said switch-board pertaining to said other telephone lines, and connecting means 'in' said switch-board whereby any link may be connected to a multiple jack of a selected line.

29. A telephone exchange system, including telephone lines extending from stations to an exchange, link circuits for uniting tele I phone lines in conversation, signal devices of said signal deviecs to alter the indications thereo f.- j

30. 'A telephone exchange system, includ-' ing telephone lines extending from stations.

to an exchange, link circuits for uniting ,telephoneflines in conversation, signal devices associated with said link circuits and operable by apparatus at, said stations, automatic selecting mechanism, including traveling contacts, for connecting the answering ends of said link circuits interchangeably with different telephone lines, and manui thereof.

ally manipulated terminals. for :said link circuits serving to act upon circuits of said signal devices to alter the indications 31, A telephone exchange system, including telephone lines extending from stations vto an' exchange, link circuits for uniting.

telephone lines in conversation, signal devices associated Withsaid link circuits and operable by apparatus at said stations, automatic selecting mechanism for connecting the answering ends of said link circuits iiiterchangeablv with diiferent telephone lines;

and manually manipulated terminals for said link circuits serving automatically to change the indication of said signal devices.

' 32. A telephone exchange system, in'cluding telephone lines extending from stations to an exchange, link circuits for uniting telephone lines in conversation. signal devices associated with said link circuits and ably with diiierent telephone lines, and manually manipulated terminals for said link circuits servingautoinaticallv to change the indication of'said signal devices.

33. Atelephone exchange system, including telephone lines extending fromstations to anexchange, link circuits for uniting telephoneklines in conversation, self-restoring signal devices associated with said link circuits and operable by apparatus at said stations, automatic selecting mechanism, iiieluding traveling contacts, for connecting the answering ends of certain of said link circuits interchangeably with different telephone lines, and operator-controlled terminals for certain of said link circuits for use in connecting the link circuits with called lines, said terminals controlling the restoration of said signals.

- 34. A telephone exchangesystem, including telephone lines extending from stations to an exchange, link circuits. for uniting telephone lines in conversation, self-restoring call signal devices associated with said link circuits, automatic selector mechanism including a traveling contact maker for connecting the it "ring ends of certain of. said link cl and said call signal devices interchangeably with different telephone lines, and operator-controlled termi-" nals for certain of said link circuits for use in connecting said link circuits with called lines and for restoring said signals.

35. A telephone exchange system, including telephone lines extending from stations to an exchange, call signal devices at the exchange, automatic selecting mechanism for interchangeably associating said call signal devices with different telephone lines, and linkcircuits having manually manipulated terminals serving automatically to change the indications ofsaid-signal devices.

'36. A telephone exchange system, including telephone lines extending from stations to an exchange, call signal devices at the. exchange, automatic selecting mechanism for interchangeably associating said call signal devices with different telephone lines,

, and link circuits having manually manipulated terminals serving to change the circuits of the signal devices to alter their indications.

- 37. .A telephone exchange system, including telephone lines extending from stations to an exchange.- link circuit for. uniting telephone lines in conversation. call signal devices associated with said link circuits, automatic selecting mechanism for connecting the answering ends of said link circu ts and-said call signal devices interchangeably with different telephone lines; and manually manipulated terminals for said link circuits for connectin said link circuits with called lines and serving automatically to alter the indications of said call signal devices.

38. A telephone exchange system, including telephone lines extending from stations to an exchange. link circuits for uniting telephone lines in conversation. call s gnal devices associated with said link circuits, automatic selecting mechanism for connecting the answering ends of said link circuits and said call signal devices interchangeably with difi'erent telephone lines, and manually 'manipulated terminals for said link circuits for connecting said link circuits with called lines and serving to change the circuits of said call signal devices to alter their indications. I

39. A telephene exchange system, including telephone lines extendin telephone lines in conversation, signal devices associated with said link circuits, au-,

tomatic selecting mechanism for connecting the answering ends of said link circuits and said signal devices interchangeably with dif ierent telephone lines, and manually inanipulated terminals for said link circuits for connecting said link circuits with called lines and serving automatically to alter the indications of said signal devices.

40. A. telephone exchange system, including telephone lines extending from stations to an exchange, link circuits for uniting telephone lines iii-conversation, signal devices associated with'said link circuits, automatic selecting mechanism for connecting the answering ends of said link circuits and said signal devices interchangeably with different telephone lines, and manually Inanipulated terminals for said link circuits for connecting said link circuits with called lines and serving to change the circuits of said signal deiiices to alter their indications.

, 4,1, In a telephone system, the combination with a line electromagnet, of a cut-oil rel ay, a plurality of trunks, an automatic selecting switch adapted to connect its wipers with said trunks successively, a source of current,

said cut-off relaywhereby the control of said automatic switch is again placedunder the control of said line electromagi'iet.

42. In a telephone exchange system, the combination with a line electromagnet, a test relay, a plurality of trunks, an automatic selecting switch adapted to connect its .wip'ers 'with said trunks successively, n

source of current, circuit connections whereby said line magnet s energized from said source of.current to start said automatic se-' lecting switch and by which said test relay is energized from .said same source of cur-'- rent to stop said automatic selecting switch with its wipers in connection with one of said trunks, a circuit by which said test relay is energized from said same source of current when the wipers of said automatic selecting switch are in contact with a now from stations ,to an exchange, link circuits for unitingbusy trunk, and means for opening said test relay circuitwhereby the sald relay deenergizes and places the said automatic selecting switch in condition for reoperation.

43. A telephone system including a metallic telephone line, aline electromagnet therefor, a central source of current for supplying talking current to said metallic line, circuit connections ,forenergizing said electromagnet from said source. of current, multiple contacts, automatic "traveling trunk hunting switch'wip'ers responsive to said electromagnet to? connect said line with idle contacts, a cut-01f electromagnet for said line, and a circuit extending from said source of current for operating said cut-ofi' electromagnet to disconnect said line electromagnet from the line, said circuit becoming effective on connection of said line with said idle contacts. I

44. A. telephone system including a metallic telephone line, traveling testing switch mechanism at the exchange, a central source of current for furnishing all necessary open ating current, an electromagnet temporarily connected with said line and source of current and operable from, the substation to control the actuation of said mechanism, switching mechanism automatically ener gized from said same source of current by the operation of said mechanism to disconnect. said ma et from the line,and means for deenergiz n said switch-mechanism to again connect't e said electromagnet to the line.

45. A telephone system including substation telephone lines, automatic testing switches, link circuits multiply connected with contacts of said switches, a source of current, means controlled at the substations and energized from said source of current for effecting operation of said switches for interconnecting said lines and link circuits interchangeably, and an electromagnet for each switch adapted to be energized from 110 said same source of current upon connection by an associated switch. with an idle trunk circuit for preventing further operation of the switch. v

46. A telephone system including telephone lines, a link-circuit at the exchange, means for uniting said lines for conversation over said circuit, said ,means including an automatic progressive idle link selector at one end of said circuit having a contact maker capable of assuming a plurality of selective positions and an operator-controlled switch at the other end thereof, and signaling means controllable from a connected substation.

47. A telephone system including telephone lines, a plurality of signals common thereto, and means including an automat c idletrunk hunting traveling switch having a contact maker capable of assuming a Plu- 130 rality of selective positions for temporarily rendering any one of certain of said signals individual to one of said lines;

48. A telephone system including telephone lines, operator-controlled link-circuits and automatic idle trunk hunting traveling switches associated ith said link-circuits and having a contact maker capable of assuming a pluralityot selective positions for tions included in the talking circuit, and a central source of talking current.

- 50. In a telephone system a telephone line, an automatic idle trunk hunting traveling switch at the exchange having a contact maker capableof assuming a plurality of selective positions, terminals for said line adapted to be included in the talking cir cuit a link circuit means for 0 eratin said J a P g .contact maker so as to connect saidterminals with said link circuit and operator controlled means for extending said line to a called line, said means including said link circuit. 51. A telephone system including a telephone circuit a battery at the exchange for supplying talking current to said circuit.

battery connections therefor, said connec tions including an electromagnet winding at the exchange directly connected with said circuit, link circuits associated with said telephone circuit, traveling switch mecha nism having a contact maker capable of assuming a plurality of selective positions operable responsive to circuit changes produced in said telephone circuit to automatically cause said telephone circuit to be connected with an idle link circuit, and a second electromagnet and switch apparatus controlled thereby automatically effective on connection of said telephone circuit with an idle link circuit ,to alter said battery connections and disconnect said electromagnet winding from the circuit, said second electromagnet being energized from said battery.

52. A telephone system including a call ing line and a called line, link circuits adapted for use in extending a conversational cir- Quit from the calling line to the called line, a common battery at the exchange for supplying talking current to said lines, an automatic switching device at the exchange in cludingtraveling mechanism having a contact maker capable of assuminga plurality of selective positions, contacts individual to the calling line included in said device,contac'ts of link circuits included in said device, and apparatus at the calling substation for closing the metallic circuit of the line through said commonv battery, said switching device being responsivethereto toautomatically connect contacts of said line operatively with contacts of an idle link circuit.

53. A telephone system including a call-- adapted for use in extending a conversational circuit fromthe calling line to the called line, a common battery at the exchange for supplying talking current to said 'lines, an automatic switchingdevice at the exchange including traveling mechanism having a contact maker capable of assuming a plurality of selective positions, contacts individual to the calling line included in sald device, contacts of link circuits included in said device, apparatus at the calling substation for closing the metallic circuit .ing line and a called line, link circuits of the line through said common battery,

said switching device being responsive thereto to automatically connect contacts of said line operatively with contacts of an idle link circuit, and an electrom'agnet for the calling line automatically effective on said connection to alter the calling lines normal circuit connections at the exchange.

54. In a telephone system, a telephone line, a manual terminal for said'line, adapted to be included in the talking circuit, an. automatic terminal for said' line at the exchange, adapted to be included in the talk-- ing circuit, manual means for establishing .connection to said manual terminal, and an automatic traveling switchhaving a contact maker capable of assuming a plurality of selective positions forestablishing connection to said automatic terminal.

55. In a telephone exchange system, the

extending from substations to an exchange,

of a plurality of trunk circuits at the exchange, each including an operator-controlled switch at one end of the trunk circuit, traveling idle trunk hunting switches associated with the other endof the trunk circuits and having a contact maker capable of assuming a plurality of selective posiconnect a trunk circuit with the telephone line of a calling subscriber.

56. In a telephone exchange system, the combination .with a group of telephone lines extending from substations to an exchange, of a plurality of trunk circuits at the exchange, each including an operator-controlled switch at one endof the trunk cir-- cuit. traveling trunk. hunting switches associated with the other end of the trunk circuits, and having a contact maker capable of assuming a plurality of selective positions, and means serving to arrest the operation of a. traveling switch and cause it to connect a trunk circuit with the telephone tions and means serving to arrest the oper- 1 ation of a traveling swltch and cause it to arresting the movement of said connecting.

station apparatus to indicate the fact of a central source of talking current;

58. In a signaling system, the combination witha subscribers station, of an operatorcontrolled link-circuit at the central station for connecting subscribers stations, a source of electricity connected to the said link-circuit and adapted to furnish transmitter currents to connected stations, means for connecting said subscribers station with said link-circuit, driven means for actuating said connecting means and means adapted to be energized by said source of electricity for means. 7

59. A telephone system comprising a substation, a metallic circuit connecting said substation with the central oflice', a central source of current for supplying talking current over said circuit, a selector switch at the exchange connected to said line including mechanism energized from said source of' current and controlled over the metallic circuit for operating said switch, link cir, cu'its for extending the talking circuit of said line and connected to contacts of said switch whereby said switch when operated will successively test said link circuits to extend connection from said line to an idle one of them and means for supplying talking current from said source through the connected link-circuit to said line.

60. In a telephone exchange system, the combination with metallic telephone lines normally open at the substations of a central source of current for supplying talking current to said lines, a trunk circuit at the central olfice common to said telephone lines,

and a rotary switch started upon the closure of a circuit from said sourceof current over the limbs of one of said telephone lines for completing the circuit between said line and said trunk circuit, substantially as described.

61. In a'telephone exchange system, the combination with a metallic telephone line normally open at the substation, a central source of current for supplying talking current to said line, a plurality of trunk circuits for the exchange, and automatic rotary means operative'upon the closure of a circuit from said source of current over the limbs of said telephone line at the substation for completing the circuit between said line and an idle one ofsaid trunk circuits, substantially as described.

.in two metallic limbs from the exchange to the substation of a source of'current at the exchange for supplying talking current to the substation normally connected in a bridge between the limbs of said telephone line, automatic switching apparatus at the exchange including a rotary switch actuated by the completion of the circuit of said source over the limbs of the telephone line, and meansresponsive to the operation of said automatic switching apparatus to bring said source intocircuit to supply talking current to said line, substantially as described.

'63. In a telephone exchange system, the combination with telephone lines each extending in two metallic limbs from the exchange to a substation, a central source of current for'supplying talking current to the substations, an idle trunk circuit at the exchange adapted to the use of'any one of said telephone lines, and a rotary device having contacts for connecting said trunk circuit and a line together and adapted to be started in rotation upon the completion of the circuit from said source of current through the limbs of said line at the substation, and means for supplying talking current from said source through said trunk circuit to said line, substantially as described.

64:. In an automatic telephone system, a central ofiice, a substation, a telephone line extending from the exchange to the substation, a source of current for talking purposes normally connected in a bridge between the limbs of said line, a plurality of trunk circuits, automatic means including a rotary switch for connecting an idle one of said trunkcircuits to said line upon completing the circuit of said source over the limbs of the telephone. line in series, and means for supplying talking current to the connected line through the associated trunk circuit, substantiallv as described;

65. In a telephone system, the combina- -tion with a subscribers station, of a pair of normally open contacts at the subscribers station adapted to be closed during conversation, an automatic rotary selector switch at the central oilice, trunk circuits at the exchange, the closing of said contacts at the substation being adapted to cause said autom'atic rotary selector switch to complete a connection between said station and an idle trunking circuit, substantially as described.

66. In a telephone system, the combination with a subscribers station and cooperating trunk circuits, of a pair of normally open contacts at the subscribers station,

' talking current fronr said source to con-.

- scribed.

67. In an automatic telephone svstem,, the combination with a plurality of telephone lines, of a plurality of trunk lines, a cen-- tral source of current, a rotary switch adapt- -ed to move to and stop upon an idle trunk line, an electromagnetic means actuated from said source of current over the limbs of the telephone line in series, for controlling said switch, and means for supplying nected telephone lines through the associated trunk lines, substantially as described.

68. A telephone system including telephone lines, extending from stations to an exchange, call signal devices at the exchange, automatic selecting mechanism for interchangeably associating said lines and signals to indicate calls, and exchange operator controlled link circuits effective when operated in extending calls, to change the signals to alter their indications.

69. A telephone. system including telephone lines, a plurality of operator controlled link cirouits, an operators telephone, talking circuit connections from said operators telephone to said link circuits, and selector switches having contact makers each adapted to be moved into a plurality or selective positions for interchangeably connecting said lines and link circuits, and

means responsive to the closing oit'the two limbs of'thetelephone lines in series for operating said contact makers to effect connection between calling lines and link circuits.

70. In a telephone system, the combination of telephone lines, trunk circuits, operator-controlled switches at the calling. end of certain of said trunk circuits, and automatic switch mechanisms associated with the answering ends of certain of said trunk circuits, said trunk circuits, operator-com trolled switches and automatic switch mechanisms cooperating in-establishing connections between telephone lines, and said automatic switch mechanisms lncluding contact makers capable'of assuming a plurality of switch mechanisms associated with the an-' swering ends of certain of said trunk circuits. said trunk circuits, operator-controlled switches and automatic switch mechanisms cooperating in establishing connections be tween telephone lines, and said automatic switch mechanisms including contact makers capable of assuming a plurality of selective positions, and signals associated With said link circuits and operable thereover to indicate the fact of the selections by said contact makers.

72. A telephone exchange system comprising a plurality of subscribers telephone lines, a plurality of associated link-circuits, automatic switch mechanism for establishing connection between a calling line and an idle link-circuit, a signal displayed upon the establishment of such connection, operators means for extending the circuit of av v selected link-circuit to a called line, and means operative upon the extension of said circuit to a called line to cause said signal to serve in a supervisory capacity.

73. A telephone system comprisiggK telephone lines, operator controlled li circuits for extending the circuits of calling to called lines, a signal for each of said link circuits, automatic switch mechanism for connecting a calling line to an idle link circuit. means responsive to such connection for lighting the associated signal to indicate the call, a supervisory relay for each link, and circuit connections including conductors of the selected link and a connected called line whereby the associated relay is operable to control said signal in a supervisory capacity.

74,-. A telephone system comprising telephonelines, operators cord circuits, a signal for each of said .cord circuits, automatic switch mechanism for-interconnecting calling lines and idle cord circuits, a relay for each cord circuit responsive tosuch a connection for operating the associated signal to indicate a call, calling plugs for the cord circuits adapted for connection with called line terminals of the lines, and a second relay for each cord circuit operable through contacts of a connected plug and called line terminal for eil'acing the signal.

7 A. telephone system comprising telephone lines, operators link circuits, a signal for each of said link circuits, automatic switch mechanism for interconnecting calling lines and idle link circuits, a relay for each link circuit and operable over the answering end thereof responsive to such a connection for operating the associated signal to indicate a call, means for extending the calling end of the cord circuit toward a called line, and a second relay for each cord circuit operable over the calling end for etfacing the associated signal.

76. A telephone system comprisin telephone lines, operators link'circuits, signal for each of said link circuits, automatic switch mechanism for interconnecting calling lines and idle link circuits, a relayfor tinuing the display of a signal when a call ing subscriber restores his telephone prior to'-' the extension of the link circuit, and a circuit controlled by the operator for again effacing said signal.

78. A telephone system comprising a telephone line, a line switch therefor, sets of progressively positioned stationary contacts for said switch, link circuits connected to said contacts, other means for rendering certain of said contact sets busy, movable contact makers for said switch responsive to a call over said line to connect the line with the first idle contact set and connected link, and means for restoring said switch by. dis-- connecting the line from the engaged contact set whereby the next call over saidline op erates said contact maker to always connect the line with the first succeeding idle contact set.

79. A telephone system comprising telephone lines, a selector switch for each line' including sets of contacts and cooperating non-normal-position progressively movable contact makers, link circuits for extending the talking circuits of said lines multiply connected to said contact sets, means included in each switch responsive to a call over the corresponding line for operating the associated contact makers to connect the calling line with the contact set of an idle link circuit, and means for restoring operated contact makers for further connection by simply disconnecting the contact makers and contacts.

80. An automatic telephone system comprising subscribers? lines, an individual- .anismcontrolled over the two sides of a line inductively isolating the limbs of said line from said source after the connection of said line with said trunk.

82. In a telephone exchange system, the combination with a-metallic telephone line normally open at the substation, a plurality of trunk circuitsfor the exchange, and automatic rotary means operatixe upon the closure of a circuit between the limbs of said telephone line at the substation for completing the circuit between said line and an idle one of said trunk circuits, substantially as described.

83. In an automatic telephone system, a central office, a substation, a telephone line extending from the exchange to the substation, a source of current normally connected in a bridge between the limbs of said line, a plurality of trunk circuits, an automatic means including. a rotar switch for connecting an idle one of said trunk circuits to said line upon completing thecircuit of said source over the limbs of the telephone line in series, and inductive means for separating the limbs of said line from said source of current after connection has been established'with an idle one of said trunk circuits, substantially as described.

84:. In a telephorie system, the combination with a telephone line of a busy trunk circuit and an idle trunk circuit, and selector means controlled by current over the limbs of the telephone line in series, adapted to move over the contacts of said busy trunk and connect said line with said idle trunk circuit, other telephone lines, and means inductively'separating each limb of said telephone line from each limb of another telephone line after connection with an idle trunk, substantially as described.

- 85. A non numerical trunk selecting 'switch mechanism comprising a pair of line wipers, a release mechanisni, a releasemagnet for operating said release mechanism and controlling the connection to said wipers,

trunk terminals to be seized by said wipers,

and a source of electrical current and connectlons therefrom for .-op'e rat1ng purposes. 86. An automatic trunk-selecting switch comprising a pair of line wipers, a cut-oil? relay, a pair of line conductors connected between said wipers and the normally closed contacts in-said relay, and a source of electrical current and connections therefrom for operating purposes.

87. In a telephone system comprising a subscribers line and trunk lines, a subscribers rotary individual non-numerical trunkmg switch for finding an idle trunk when the subscriber removes his receiver in initi- 4 88. In a telephone system comprising a subscribers line, and trunk lines, a subscribers rotary individual trunking switch for seizing an 1dle trunk line when the subscriber calls, an electromag'net included in 7 said switch for releasing purposes, an energizing circuit for said electromagnet including one conductor of any trunk line seized, by said switch, a central source of current for furnishing all necessary operating cur rent and for supplying talking current to the subscribers line, and a cut-off relay for interrupting the normal connections between said source-and said line when connection is made with the line as a called line.

89. In a telephone system, a subscribers line, a rotary non-numerical trunking witch for said line comprising trunk terminals, line terminals, means for releasing the line terminals from the trunk terminals including release trunk terminals corresponding to the trunkterminals, and-a central source of current for furnishing all necessary operating current and for upplying talking battery to the subscribers line.

90. In a telephone system, a subscribers line, a non-numerical trunking switch for said line comprising only a single row or level of trunk terminals, a row of release trunk terminals corresponding thereto, a

source of electrical current and connections therefrom for operating purposes and for supplying talking battery to said subscr1bers line, and a cut-off relay for interrupting the normal connections of said battery .with said line when connection is estaband an idle link-circuit, and means independent of the position of the contacts of the operated switch for rendering the selected link-circuit selectable by. other switch mechanisms.

93. A telephone exchange system comprising a plurality of telephone lines, a plurality.

of associated link-circuits, a plurality of switch mechanisms individually operative to establish connection between a calling telephone line and an idle link-circuit, and means for rendering the selected link-circuit selectable by other switch mechanisms independently of the return of the operated switch mechanism to normal.

9i. A telephone system comprising a subscribers individual trunk selecting switch provided with a contact maker capable of assuming a plu tlity of selective positions, a plurality of trunk lines leading from said switch, means at the end of each trunk line for extending a connection, subscriber means for operating said individual switch to select an idle one of said trunk lines, said individual switch being provided with relay means adapted to remain energized during the use of'the switch for talking purposes,

and means associated with each of said trunks for controlling-the duration of energization of said relay means.

95. A telephone system including a calling subscribers line and a called subscribers' line, a trunk selecting switch provided with a contact maker capable of assuming a plurality of selective positions, a plurality of trunk lines leading from said-switch, connective apparatus at theend of each trunk line, subscriber means for operating said trunk selecting switch, said "switch being provided with a relay that remains energized during the use of the switch for talking purposes, and means associated Witheach of said connective apparatuses for controlling the duration of energization of said relav.

96. A telephone system comprising subscribers lines, rotatable progressively movable automatic switches provided with contact makers capable of assuming a plurality ofselective positions, electromagnets normally bridged across said lines for controlling said switches, a talking circuit included in said lines, said talking circuit being at all times free from inductive resistance in the path of the talking currents at said automatic switches, means for cutting ofi or opening up the bridges in which said electromagnets are located when the two lines are connected up for conversational purposes, and a centralized source of currentsupply for furnishing talking currents to the subscribers lines and for also furnish ing the current necessary for operating the said electromagnets before the bridgesot the latter are cut off or opened up.

97. A telephone system including calling and called subscribers lines connected up for conversation, a rotatable progressively movable automatic switch provided with a llb contact maker capable of assuming a plu-' rality of selective positions included in said connection, one or more electromagnetic bridge located at the exchange and temporarilycut off from the talking circuit during conversation, the talking circuit being free from inductive resistance at said automatic switch, and a centralized source of current-supply connected to furnish talking current to the subscribers lines.

98. A telephone system including calling and called subscribers lines connected up for conversation, a rotatable automatic switch provided with a contact maker capaw ble of assuming a plurality of selective positions included in said connection, electromagnets normally bridged across the talking circuit but operatively disassociated therefrom during conversation, the talking circuit being free from inductive resistance in the path of the talking currents at the said fore the call reaches the called line.

' 100.- In a telephone system, a trunk-line,

a called line, a calling line, means for extendinga call from a calling to a called line, said means including a line electromagnet, switch-mg means controlled by said electromagnet, said switching means being provided with a contact maker capable of assuming a pluralityof selective positions,

: a cut-ofi' relay, and means controlled over the trunk-line for operating said cut-off relay, responsive to the calling subscriber, to operatively disassociate by a single movement the line electromagnet before the call reaches the called line.-

101. A telephone system comprising a calling line, a called line, means for extending a call from a calling line to a called line, said means including a trunk-line, a bridge including. an electromagnetic switch operating'element, a contact maker capable of assuming a plurality of. selective positions. a controlled by said switch operating. element,

a bridge cut-oif relay, and means controlled over the trunk-line for operating said relay, responsive to the calling subscriber, to open by a single movement said bridge before the call reaches thecalled line.

102. In a telephone system, means for e."- tablishing a talking circuit between a calling and a called subscribers line, said means including an automatic trunkselecting switch f selecting idle trunks and a single wound relay for controlling said circuit, and means by which the calling subscriber energizes said relay before the call reaches the called line to maintain the continuity of the circuit during use of the same fortalking purposes. I

103. In a telephone system, a calling subscribers line, a called subscribers line, means for establishing a talking circuit between said lines, said means including an automatic switch provided with a contact maker capable of-assuming a plurality of selective positions, a single wound relay for said switch for controlling said circuit, and means by which the calling subscriber causes said relay to be energized before the call reaches the called line to maintain the continuity of the circuit during use of the same for talking purposes.

104:. In a telephone system, a calling sub' scribers line, a called subscribers line, means for establishing a talking circuit between said lines, said means including an automatic switch individual to the calling subscribers line provided with a cont-act maker capable of assuming a plurality of selective positions, a single wound relay for said switch, and means by which the said relay is energized before the call reaches the called subscribers line to maintain the continuity of the circuit during use of the same for talking purposes. I g

.105. In a telephone system, a calling line, a called line, means including an automatic switch provided with a contact maker capable of assuming a plurality of selective positions for extending a-call from the calling line in the direction of the called line. a

line electromagnet and a cut-offv relay for said automatic switch. and means controlled over the calling line for operating said out- 01f relay responsive to the calling subscriber to disconnect by a single movement the line electrbmagnet before the call reaches the called line.

106. In a telephone system, a trunk line, a called line, a calling line. means including an automatic switch provided with a contact maker capable of assuming a plurality of positions for extending a call from the calling line to the said trunk line. a line electromagnet and a cutoff relay for said automatic switch, and means controlled over the trunk line for operating said cut-off relay responsive to the calling subscriber to operatively disassociate by a singlemovement the line electromagnet before the call reaches the called line.

107. A telephone system including telephonelines, interconnecting link circuits, a selector switch for extending both limbs of the talking circuit of a calling line to an idle link circuit, saidselector switch being confor use in selecting the idle link circuit, and

cluded in said talking circuit, a circuit for releasing said switch mechanism including said testingcontact, means for controlling said circuit, and 'a source of current for supplying current'for operating and talking purposes.

109. A telephone system including telephone lines, interconnecting linlncircuits, a selector switch for extending both links of the talking circuit of a calling line to an idle link circuit, said selector switch being controlled over the two sides of the calling line in series and provided with a test contact for use in selecting the idle link circuit, means for restoring said switch to normal including a circuit extending through said testing contact, and a central source of current for furnishing all necessary operating and talking current.

110. In a telephone system, the combination of a subscribers line comprising two metallic conductors, another subseribers line, a plurality of trunk lines any one of which will serve to'establish connection between said lines, a trunk selector provided with a contact maker capable of assuming a plurality of selective positions for automatically selecting an idle one of said trunk lines, a magnet for controlling said selector included in abridge across the conductors of said first line and controllable over the sides of said line in series, and a source of current for supplying current for operating purposes and fortalking purposes.

111. In a telephone system, a line, another line, each having two metallic limbs, a plurality of trunks any one of which will serve to build up a connection between said lmes, a trunk selector, a' magnet for controlling said selector included in a bridge across the metallic limbs of said first line and controlcontrolling said selector included in a bridge across the metallic limbs of said first line and energized over the two sides of the line in series, means for causing said trunk selector to automatically connect said first line with an idle one of said trunks. said bridged magnet also being adapted to control the release of said selector;

113. In an automatic telephone system, two lines each having two metallic limbs, a plurality of trunk lines any one of which will serve to establish connection between said lines, a trunk selecting switch provided with a contact maker capable of assuming a plurality of selective positions, a pair of controlling magnets in a bridge across the metallic conductors of said line, means-for operating sa1d magnets to cause said switch to select an idle one of said trunks, means for opening said bridge upon finding an idle trunk, the release of said switch being controlled by both of said bridged magnets, and a source of current for supplying current i for operating and talking purposes.

114. A telephone system including telephone lines, an interconnecting link circuit, a switch mechanism provided with a contact maker capable of assuming a plurality of selective positions for uniting a calling and a called line by the link circuit into a talking circuit, an electromagnet in a bridge across the conductors of said talking circuit at said switch mechanism for controlling its operation, a testing contact associated with said switch mechanism for selecting the link circuit to be included in said talking circuit, a circuit for releasing said switch mecha nism including said testing contact, means for controlling said circuit, and a centralsource ofcurrent for supplying current for operating and talking purposes.

115. In a telephone system, the combination with a substation telephone line, of trunk lines, an automatic progressively movable line switch for said line operative upon initiation of a call from said line to select an idle one of said trunks, a cut-01f relay for said line energized after connection with said trunk, and means associated with the selected trunk to deenergize said relay, whereby said switch is released.

116. A telephone system comprising a substation telephone line, trunk lines, an automatic line switch for said line provided with a movable contact maker capable of assuming a plurality of selective positions and operated responsive to the removal of the telephone receiver in the initiation of a call over said line to select an idle one of said trunks, a cut-oil? relay for said line, means associated with said trunk for energizing. said cut-0E relay responsive to said selection, said means being also operable to (leenergizc said relay, and release means for said switch thereby rendered effective.

1111A; telephone system coinprising afaccessible to said ;s' substation telephone line, trunk l1nes;'a con lease'saidswiteh. v 1 .s

1 118; A'l'ine; switch for a telephone system- -selected-. t rnnk-'11n T switch for saidlineoperated responsive o 7 said control relay to-select an 1dle-o trunk for energizing said cut o fi' relay; and? restoring m 'ea'n's for inovmg a-id *wipei s [for telephone system t'rol 'rela'yforsaid line, a non n-um'eri'ca fcircuit ijncludinga conductor. of;. these1ected-;j

means associated w th said trunk c6na o;1 lable to de'nergize said cut-oft" relayto re compri'singcontacts and; coiiperatin'g wipers; "123'," A fnon -resto v 9 1 m ii i iw s fronien'gagement with a set of selected con-v --tacts andfeooperatin wipers, 'm'otor'rnecha tactss-trnnlrlines, a'inotor magnet operating nisin.for" operati gfaid wi f im 1 'trunk-lines a cufloff-relayinaintainedieners I I I II I II gizedfover a conductor-o1- vsa dj selected-1 l qyj tlle contactsfof saidrelaysior' 'operating I -'-re1ay, or operating said jrest0r1ng'f-1n eans storingisald'sw1tch;:y.

.i "whensaid relay denergizes; t I

(having individually} i -.control-led said, wipers to 'select .an idle onejof/said-' lays"'.ea I I II I II I II I I I and c rcu t connectldlls [controlled and Im'eans.

trunk; ontrol-led by said, cut-0&5" said; motor; mechanism I and i i 2 1 'non 'nninericaL-f' "wiper l ne; switch: "comprising bank. termi 1119,; In. a telephone system,

tiiegjetmbina tion with} substation;telephone 11118',' of nals and OtSperatin-g Jwipers, relays .con-v trunklines, an automatic switch for said tacts for-[saidrelays-"said contacts beingine, line-operated upon initiation'of a ca-lltfrom; clividnallycontrolled hyztheir.respective resaid l ne to select; an idle oneloi'jsaidtrnnks, *laysimotormechanism for operating said I H means for naintainingsaid switch inzaselec wipers,"and circiiit"'connections controlled 'tiYe' positionfa'cut-ofi relay" for said line by the'eontact's-ofsaid. relays for operating maintained energized; over:v a conductor of: said-motormechanism-and wipers to select a, said'trn'nk after connection withsaid-trunk, .jsetof said bank termlnalsandrestoring said "and' means for denergizingvsaid" -:i'elay" switch;

whereby said maintaining means is operated A lines and a group of to permit the said switch to inovefrom its ,trunks-lesslnnlimber than the number of ,3'5

lines, individual inoving element for selective-position. t I .7

each line, multiplyv connected stationary ele- 120 In a tlephpile VI with a. siibstationtelephone line allv a O'i s -Q fl hr fmeanscause the hatic SWltCh,'i ldlvldual th e e t l nwvable e m ntsf lme to e nn with relay for said ll i energized P lmtlatlon' thflmultlpll' connected a y" of a call at said'substation, said switch beelementsofza trnnk, and-means for'causing .ing responsive to the energlzation of said themo'table elementof the lin'eto assume a [co1'1t1'ol,relay to extend the circuit of said position"nntil nextnsed between the, stationline tO'an idle trunk, a cut-off relayfor saidi "ary eleinentrof'the trunk last used and the lay whereby. I frointsaidtrunk' line.

linemaintaine'd energized over a conductorstationary element offthe next trunk when of said trunk upon anextension of saidline, disconnection is made beween the-line a d; 11d andmeans for denergizing sald cut-off reits lastused trunk the said line is disconnected 126LA telephone 121; In a telephone-s steni, a combination rel'aytforsaid-lineenergizedupon-initiation "connect; and means to} disconnect the line I 1 of a call atfsaid substation}saidswitch be wipers from t-heircon'nected pair until again v ingresponsivefflto thsfenergizationof, said jtaken for *nse by adVancing the said line control relaygto 'extend the"c1rcn1t of said wlpers to a ,positlo'n between the pair of .line 'to'vanj'idleatrnnk; a cut-on. relay for trunk contacts'lastlnsedand the next pair of said line maintained energized overfacontrunk contactsgi I 1 ductor of said trunk uponanextensionof I 127'. A telephonj. system 'fcornprising a saidjline; and nieansfordenergizin saidtelephone line and a rotary line switch for cut-ofi' arela'yf whereby thewipersjo said extending 'connectioi ff aid. line to any switch are operated to disconnect th" said telephone'li'n'e fronitsaid-triinkli-n 122. A 1 telephone system; compris ng swbscribefisf, lin vp avid-eaten a} on n erical trunlcsw itch I I line extending. in twof I 'fjl n bs fr'or'n'al substation to a central ofiice, a, pair of line wipers-.eonnected'with the'limbs- H .i fith a Substation t p cne ne; u line, a pl r y of'p r t' I .-n1atic"switoh; individual itheretopa', .con'trol'flcontactswithjwhichfg id li wi may 128. In a telephone system the combination with trunk lines, of a plurality of switches at which said trunk lines are available, the

the trunk contacts at said switches by retaining the contacts'of said idle switches in positions between the contacts of the trunks last used and the next available set of trunk contacts.

' 129. A, rotaryswitchfor interconnecting Copies of lthis patent may he obtained for five cent: each, by dialing and Washington, 1). 0.

the diiierent links of a circuit, comprising 15 used and the next succeeding set of station- 20 ary contacts when disconnection is desired. In witness whereof, I hereunto subscribe my name this 16th day of July A. 1901.

HAROLD D. STROUD. Witnesses: I

GEORGE L. Canoe,

HARVEY L. Henson.

colnnillloner of 1mm.

toand stop them'in a 

